This document contains code for initializing and sending data to an LCD module using a PIC microcontroller. It includes macros and subroutines for initializing the LCD, sending control signals and data, and displaying the message "HOLA MUNDO" on the LCD screen. When the user presses a button, the display will be cleared and the message will redraw.

1. INCLUDE <P16F628A.INC>
CBLOCK 0X20
R0C,R0D,R0E,R13,loops,loops2,REG_RX,CONTE,MEMORIA,RX_COMP,RX_ID1,RX_ID2,R
X_PRO1,MENS_CONT,CON_USER,DATA_IN,CONT_USER,
CONT_INTS,MEM_STATUS,DATA_RUP,DATA_COMP,ID1_SAVE,ID2_SAVE,ID3_SAVE
ENDC
E EQU 2H ; A LA PATA 6 (E) HABILITACION DEL MODULO
RS EQU 1H ; A LA PATA 4 DEL MODULO (RS - INSTRUCCION O
CARACTER)
; PATA 2 DEL MODULO A +VCC
; 3 REGULA CONTRASTE, AL PM DE UN POTE 5K
ENTRE VCC Y MASA
; 5 Y 1 A MASA
;PATA 6 DEL PIC----->A LA 4 DEL M�DULO
; 7----> 6
; 10--->11
; 11--->12
; 12-->13
; 13-->14
;retardo para COMUNICACI�N CON M�DUL0 LCD
ORG 0X00
GOTO INICIO
RETARDO
CLRWDT
MOVLW D'15' ;antes 15
MOVWF loops
top2_1
MOVLW D'25' ;antes 25
MOVWF loops2
top_1
CLRWDT
NOP
NOP
NOP
NOP
NOP
NOP
DECFSZ loops2,1 ;pregunta si termino 1 ms
GOTO top_1
DECFSZ loops,1 ;pregunta si termina el retardo
GOTO top2_1
RETLW 0
CONTROL
CLRWDT
BCF PORTB,RS ;ESTA RUTINA GENERA LAS
GOTO DATO2 ;SE�ALES DE CONTROL Y ENVIA
DATO
CLRWDT
BSF PORTB,RS ;EL DATO Al MODULO

2. DATO2
BSF PORTB,E ;CON INTERFACE DE 4 BITS
MOVWF R0E
MOVLW 0FH
ANDWF PORTB,1
MOVF R0E,W
ANDLW 0F0H
IORWF PORTB,1
CALL RETARDO
BCF PORTB,E
CALL RETARDO
BSF PORTB,E
MOVLW 0FH
ANDWF PORTB,1
SWAPF R0E,W
ANDLW 0F0H
IORWF PORTB,1
CALL RETARDO
BCF PORTB,E
CALL RETARDO
RETLW 0
;------------------------------------------------------
;*********************************
INICIO
BSF STATUS,5
CLRF TRISB
MOVLW .255
MOVWF TRISA
BCF STATUS,5
CONFI_LCD
MOVLW 02H ;INICIO DEL MODULO A 4 BITS
CALL CONTROL ;
MOVLW 28H ;4 BITS Y DOS LINEAS
CALL CONTROL ;
MOVLW 0CH ;ACTIVA EL DISPLAY
CALL CONTROL
MOVLW 06H ;MENSAJE FIJO,SIN ROTAR
CALL CONTROL
ENTRADA
BTFSS PORTA,0
GOTO BORRA_LCD
MENSAJE
MOVLW 01H ;BORRA DISPLAY
CALL CONTROL
CALL RETARDO
MOVLW " "

3. CALL DATO
MOVLW " "
CALL DATO
MOVLW " "
CALL DATO
MOVLW " "
CALL DATO
MOVLW " "
CALL DATO
MOVLW "H"
CALL DATO
MOVLW "O"
CALL DATO
MOVLW "L"
CALL DATO
MOVLW "A"
CALL DATO
MOVLW " "
CALL DATO
MOVLW "M"
CALL DATO
MOVLW "U"
CALL DATO
MOVLW "N"
CALL DATO
MOVLW "D"
CALL DATO
MOVLW "O"
CALL DATO
MOVLW " "
CALL DATO
MOVLW " "
CALL DATO
MOVLW " "
CALL DATO
MOVLW " "
CALL DATO
MOVLW " "
CALL DATO
CALL RETARDO
GOTO ENTRADA
BORRA_LCD
MOVLW 01H ;BORRA DISPLAY
CALL CONTROL
CALL RETARDO
GOTO ENTRADA
END